Consider again the average speed s(x) and its linear approximation L(x) discussed in Example 1. The error in using L(x) to approximates s(x) is given by E(x) = |L(x) - s(x)|. Use a graphing utility to determine the (approximate) values of x for which E(x) ≤ 1. What does your answer say about the accuracy of the average speeds estimated by L(x) over this interval?